Clark's Nutcracker (Nucifraga columbiana) - HBW 14, p. 612

Taxonomy:Corvus columbiana A. Wilson, 1811, two miles [3.2 km] north of Kamiah, on Clearwater River, Idaho, USA. Probably derived from a Siberian form of N. caryocatactes which crossed the Bering land-bridge, perhaps as relatively recently as 1.5-2 million years ago. Monotypic.